1. Field of the Invention
The present invention relates to an automatic transmission. More particularly, the present invention relates to a damper clutch control apparatus of an automatic transmission and a method for the same which may realize active release of a damper clutch.
2. Description of Related Art
As drivers have wanted a vehicle convenient for driving, automatic transmissions have been widely used. However, an automatic transmission uses a torque converter of low efficiency, and thus, compared with a manual transmission, it has a critical drawback in fuel consumption.
Accordingly, in order to simultaneously provide the convenience of the automatic transmission and the efficiency of the manual transmission, a damper clutch that directly connects a pump axis of a torque converter with a turbine in a predetermined driving condition has been provided.
The damper clutch directly connects or releases the pump axis and the turbine so as to prevent deterioration of the fuel consumption due to a power loss that is generated by a rotation-speed difference between the pump axis and the turbine axis above a predetermined vehicle speed.
An automatic transmission is provided with a predetermined map of which operation condition and disoperation condition of a damper clutch is stored and the operation condition and the disoperation condition of a damper clutch is determined according to input torque (engine torque value*torque ratio of a torque converter) and slip amount, which are calculated based on a throttle opening, turbine speed, engine speed and vehicle speed.
If the operation condition of a damper clutch is damper clutch is satisfied, a solenoid for the damper clutch is operated to operate the damper clutch and thus efficiency of a manual transmission and convenience of an automatic transmission may be realized.
For determining the map for controlling the damper clutch of the automatic transmission, a damper clutch release line of transient state for engaging and disengaging is determined opening amount of a throttle valve. And in a low speed, the damper clutch release line is determined relatively low due to booming.
The booming means a vibration noise which is generated according to increasing of turbine speed change rate in engagement of the damper clutch.
In a conventional art, when the damper clutch is connected, fuel consumption may be enhanced. However, a driver's intention for acceleration may not be in reflected.
Also, if the disengagement condition of a damper clutch is damper clutch is satisfied, the connection of the damper clutch is release immediately, and thus vehicle's deviation and various load conditions are not in reflected, acceleration may not be satisfied, and shock may be occurred.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.